Instructions
Line an 8-inch square baking pan with wax paper or aluminum foil. Make sure the paper or foil covers the bottom and all sides. Spray the lined pan with non-stick cooking spray.
Spread 1/2 cup of miniature marshmallows evenly over the bottom of the prepared pan.
In a large microwave-safe bowl, combine the chocolate chips and peanut butter. Microwave for 20 seconds. Remove the bowl and stir well. Return to the microwave for another 20 seconds. Stir again. Repeat this process until the mixture is completely smooth and melted. Be careful not to burn the chocolate. This usually takes about 1 to 2 minutes total.
Stir the vanilla extract into the melted chocolate mixture. Mix until it is fully combined.
Set aside 2 tablespoons of the chopped peanuts. These will be used for the topping.
Add the remaining 1 1/2 cups of miniature marshmallows to the chocolate mixture. Add the rest of the chopped peanuts (all but the 2 tablespoons you set aside). Gently fold these ingredients into the chocolate mixture. Mix until just combined, do not overmix.
Pour the chocolate mixture into the prepared pan. Use a spatula to spread it evenly. Immediately sprinkle the 2 tablespoons of reserved chopped peanuts over the top.
Place the pan in the refrigerator. Chill for at least 4 hours. The fudge should be firm to the touch when ready.
Once firm, remove the pan from the refrigerator. Lift the fudge out of the pan by holding the wax paper or foil. Carefully peel the wax paper or foil away from the fudge. Place the fudge on a cutting board. Use a sharp knife to cut the fudge into small, bite-sized pieces. Serve immediately or store in an airtight container.